You haven't seen any of the British Battleships either, but I bet they are in as well.
Why would they take out a working sea state included in the previous games, and just have light/medium waves? Considering you get to travel the whole atlantic, med and more, whole year around.
Trying to take that out of the code would be more harder than you think. So I'm confident there are rough seas.
The things they didn't include (subs other than VII, campaign after 1943) must be related to the new interior/crew system. They couldn't get the other sub interiors completed, and they couldn't get the new crew/gadgets to work with the new technology, in the detail they wanted to simulate. (Either from time constraints or future plans..)
IMHO some goodies are kept for suprise
